title: Effects of a zirconate coupling agent incorporated into an experimental resin composite on its compressive strength and bonding to zirconia.
abstract: OBJECTIVE
  To assess in vitro the compressive strength of an experimental zirconate coupling agented resin composite and its bonding to dental zirconia ceramics.
  
  
  METHODS
  Various ratios (1.5-4.0wt%) of a zirconate coupling agent, NZ-33(®), zirconium(IV)-2,2[(bis-2-propenolatomethyl)butanolato-tris-2-methyl-2-propenoato-O)] were incorporated in an experimental bis-GMA/MMA-based resin composite formulation with silica fillers. Compressive strength of the experimental resin composite and shear bond strength (SBS) of the resin composite to zirconia were evaluated by using a universal testing machine. Specimens were stored in dry condition, in water storage for 7 days and for 14 days, to a total of twenty test groups. The data were analyzed by one-way ANOVA and Tukey post hoc test (α=0.05).
  
  
  RESULTS
  SBS of resin-to-zirconia bonding and compressive strength both have significant increase at 1.5wt% and 3.0wt% NZ-33(®) (p<0.05). However, water storage for 7 days (p>0.05) and 14 days (p>0.05) significantly decreased SBS of the experimental resin-to-zirconia with no significant difference between groups (p>0.05).
  
  
  CONCLUSIONS
  An addition of a zirconate coupling agent used might strengthen the biomechanical properties of the experimental resin composite.
authors.affiliation: Dental Materials Science, Faculty of Dentistry, The University of Hong Kong, Hong Kong Special Administrative Region, PR China. Electronic address: wdc1213@hku.hk.
authors.forename: Jonathan Dai Cheung
authors.initials: JD
authors.lastname: Wong
authors.forename: Christie Ying
authors.initials: CY
authors.lastname: Kei Lung
authors.forename: James Kit-Hon
authors.initials: JK
authors.lastname: Tsoi
authors.forename: Jukka Pekka
authors.initials: JP
authors.lastname: Matinlinna
mesh_terms: D019245:Compressive Strength; D012117:Resins, Synthetic / Q000737:chemistry*; D012822:Silicon Dioxide / Q000737:chemistry; D013499:Surface Properties; D013997:Time Factors; D014867:Water / Q000737:chemistry; D015040:Zirconium / Q000737:chemistry*
chemical_list: D012117:Resins, Synthetic; D014867:Water; D012822:Silicon Dioxide; D015040:Zirconium; C028541:zirconium oxide
keywords: Adhesion; Coupling agent; Resin composite; Shear bond strength; Zirconia